import koji

mytag = "mytag"
session = koji.ClientSession("http://koji.koozali.org/kojihub")
try:
    repo_info = session.getRepo(mytag, koji.REPO_STATES["READY"], dist=True)
    if not repo_info:
        print(f"There is no active dist repo for {mytag}")
except koji.GenericError:
    print(f"Tag {mytag} doesn't exist")